Aside from what Raincoaster said, if you are looking for images to appear in your internal search results (for example, this: http://theslylockfiles.wordpress.com/?s=mouse ), the answer is "sort of". You can see that some themes have it by default:

So if you can find a theme that you like that has images in search results, then you are good to go.

There are ways to do it with a self-hosted blog (such as the Get the Image plugin). And you could also find/hack/modify a theme that has images in search results (or force it to via the aforementioned hacking/modifying). But that is a whole different ball of wax and may not be what you are looking for.